Method of performing automatic commissioning of a network

ABSTRACT

The invention describes a method of performing automatic commissioning of a network (N) comprising a plurality of network devices (10, 11, 12, 13), wherein each device (10, 11, 12, 13) is characterised by a device identifier (14) and wherein the devices (10, 11, 12, 13) are realised to exchange data packets (2), which method comprises the steps of obtaining a computer-readable installation plan (3) for the network (N), which installation plan (3) comprises a physical location descriptor (31) for devices (10, 11, 12, 13) of the network (N); deducing the network topology (T) of the network (N) from network descriptive information (40, 41, 42, 43) provided by the devices (10, 11, 12, 13) on the basis of data packets (2) exchanged between the devices (10, 11, 12, 13); and comparing the deduced network topology (T) to the installation plan (3) to allocate a physical location descriptor (31) to a device identifier (11). The invention further describes a commissioning system (1) for automatically commissioning a network (N) comprising a plurality of network devices (10, 11, 12, 13), wherein each device (10, 11, 12, 13) is characterised by a device identifier (14) and wherein each device (10, 11, 12, 13) is realised to transmit and receive data packets (2), which commissioning system (5) comprises a source (50) of a computer-readable installation plan (3) for the network (N), which installation plan (3) comprises a physical location descriptor (31) for each device (10, 11, 12, 13) of the network (N); a device control interface (55) realised to collect network descriptive information (40, 41, 42, 43) provided by the devices (10, 11, 12, 13); a topology discovery unit (53) realised to derive the network topology (T) of the network (N) from the provided network descriptive information (40, 41, 42, 43); and a commissioning unit (54) realised to compare the derived network topology (T) to the installation plan (3) to allocate a physical location descriptor (31) to a device identifier (14).

CROSS-REFERENCE TO PRIOR APPLICATIONS

This application is a Divisional Application of U.S. Ser. No. 13/880,071filed on Apr. 18, 2013 which claims the priority benefit under 35 U.S.C.371 of International Patent Application No. PCT/IB2011/054534, filed onOct. 13, 2011, which claims the priority benefit of European Application10188455.9, filed on Oct. 22, 2010, the contents of which are hereinincorporated by reference.

FIELD OF THE INVENTION

The invention describes a method of performing automatic commissioningof a network, and a commissioning system for automatic commissioning ofa network.

BACKGROUND OF THE INVENTION

Many commercial, public or industrial buildings with many levels andmany rooms avail of a control system for controlling the lighting,ventilation, air-conditioning etc. Devices such as lights or luminaires,light switches, light sensors, thermostats etc. with networkingcapability can be installed as part of a device network that can becentrally and automatically controlled. In a typical building such as alarge office complex or a hospital, the device network may comprise manyhundreds or even thousands of devices or nodes. Devices may be wirelessand can communicate using a suitable wireless protocol. In a wirednetwork such as an Ethernet network, neighbouring devices are physicallywired together using a suitable connector such as a twisted pair or aco-axial cable. A ‘branch’ of a network refers to a number of deviceswired together in series.

To set up such a wired network, the devices are first wired togetheraccording to a predefined plan. For example, a certain group ofluminaires, for example all the luminaires in one room, can be wiredtogether with a light sensor in a daisy-chain configuration. Eachluminaire and sensor can be realised as simple bridges, i.e. with onlytwo ports. One luminaire of the group of luminaires can in turn be wiredto a ‘switch’ or hub located, for example, in a corridor outside thatroom, whereby the term ‘switch’ should not be confused with a ‘lightswitch’ or other manual switch, but is used in the context of amulti-port bridge. The hub in turn can be wired to other hubs orbridges. The order in which the devices are to be connected is usuallyspecified on a plan generated using a program such as AutoCAD, which anelectrician can consult while carrying out the wiring. The wired networkthen comprises a plurality of nodes (the devices) connected by branches(the connecting wires), whereby the nodes can be sent and receivemessages (data packets) along the branches of the network.

Usually, the luminaires, sensors etc. of the network are controlled bysome suitable control system running on a server, whereby the devicescan be individually or collectively controlled by the control system. Anexample of a prior art dedicated lighting control system operates on astandard such as a digital addressable lighting interface (DALI) for thecontrol of lights. In order to be able to correctly control the devicesaccording to the wishes of the building's occupants or management, thecontrol system must be informed as to which device is located at whichphysical location in the building. For example, in order to be able toswitch on or off the lights in a particular room on a particular level,the control system must known which lights are located in that room.Giving the control system this information is referred to as‘commissioning’, which is performed after the electrical installation ofpower cables and data cables has been completed. Unfortunately, theknown methods of performing commissioning involve much manual input, andare time-consuming, labour-intensive and error-prone. In fact, thecommissioning of a prior art lighting control system such as a DALIsystem can constitute up to one third of the total cost of the system.

Therefore, it is an object of the invention to provide a more reliableand cost-effective way of commissioning a network.

SUMMARY OF THE INVENTION

This object is achieved by a method according to claim 1 of performingautomatic commissioning of a network, and by the commissioning systemaccording to claim 10.

According to the invention, the method of performing automaticcommissioning of a network comprising a plurality of network devices,wherein each device is characterised by a device identifier and whereinthe devices are realised to exchange data packets, which methodcomprises the steps of obtaining a computer-readable installation planfor the network, which installation plan comprises a physical locationdescriptor for each device of the network, deducing the network topologyof the network from network descriptive information provided by thedevices, and comparing the deduced network topology to the installationplan to allocate a physical location descriptor to a device identifier.

In the context of network devices, the ability to ‘exchange datapackets’ means that a device of the network can send or broadcast a datapacket, and can receive a data packet. A sent data packet can be sent toa specific device or can be broadcast to all devices in a position toreceive it. The device identifier of a device can be any suitable meansof identifying the device of the network, for example a code that isunique to that device and which can be included in any data packetbroadcast or sent by that device to mark that device as the originatorof the data packet. Similarly, the device identifier of a target devicecan be included in a data packet as the ‘address’ of that target device.The computer-readable installation plan can be in any suitablemachine-readable format and can have been generated from any suitablecomputer-aided drafting program, for example AutoCAD. A physicallocation descriptor for a device can be any suitable tag or code such asan alphanumeric sequence giving the physical location of that device,for example an alphanumeric sequence giving the building level, the roomnumber and the position in that room for that device. The advantage ofthe method according to the invention is that the network descriptiveinformation provided by the devices can be analysed entirelyautomatically to deduce or discover the network topology, and, togetherwith the installation plan, the physical location descriptor of eachdevice can easily and quickly be identified. In this way, each device ofthe network can be matched to its unique physical location descriptor.In other words, using the method according to the invention,commissioning can be carried out entirely automatically without anylabour-intensive and expensive manual input. This information in turncan be used, for example by a system controller, to control specificdevices of the network according to the requirements of the user(s).

According to the invention, the commissioning system for automaticallycommissioning a network comprising a plurality of network devices,wherein each device is characterised by a device identifier and whereineach device is realised to transmit and receive data packets, whichcommissioning system comprises a memory for storing a computer-readableinstallation plan for the network, which installation plan comprises aphysical location descriptor for each device of the network; a devicedatabase for storing a device identifier for each device of the network;a data input unit for inputting network descriptive information providedby the devices; a topology discovery unit for deriving the networktopology of the network from the provided network descriptiveinformation; and a commissioning unit for comparing the derived networktopology to the installation plan to allocate a physical locationdescriptor to a device identifier.

Since the commissioning system according to the invention is not limitedto use with any particular network standard or device control interfacestandard, the inventive commissioning system can advantageously use thecapabilities of a commercial off-the-shelf (COTS) computer networkingtechnology to commission the network.

The dependent claims and the following description disclose particularlyadvantageous embodiments and features of the invention. Features of theembodiments may be combined as appropriate to arrive at furtherembodiments.

While each device can both send and receive data packets, in thefollowing and for the sake of convenience, a device that has received adata packet may be referred to as a ‘receiving device’, while a devicethat has sent or broadcast a data packet may be referred to as a‘sending device’. Data packets can be sent or received by such a deviceover a network interface card (NIC) built into the device. A datapacket, command or message is usually assembled or compiled by a sendingdevice in a predefined frame structure, so that a receiving device candetect the beginning and end of a frame and can extract specificinformation fields from the frame.

Preferably, the device control interface of the commissioning system isrealised to control devices of a wired network. For example, the devicesare preferably wired together in an Ethernet TCP/IP network.

Devices of a network such as a frame-based local area network canusually both send and receive data packets or frames. Therefore, in apreferred embodiment of the invention the network descriptiveinformation is accumulated by devices of the network on the basis ofdata packets sent and received by those devices.

Since the devices in a network are usually identified uniquely at leastin that network by their device identifier, in a preferred embodiment ofthe invention the network descriptive information accumulated by areceiving device comprises a list of device identifiers, wherein eachdevice identifier entered into the list indicates a device thatbroadcast a data packet received by the receiving device. In this way,each receiving device can compile or assemble a list of deviceidentifiers from which it has received one or more data packets. Ineffect, such a list specifies the devices to which the receiving devicecan also forward data packets, and may be referred to as a ‘forwardingtable’. The device identifier can be any suitable code, uniquelyidentifying that device at least in that network, such as a 128-bitInternet protocol address (IP address) or a 48-bit media access controladdress (MAC address). As will be known to the skilled person, such anaddress can be permanently stored in the firmware of the device, or onits network interface card, in a read-only memory of the device, etc.

A device of the network may be a router or bridge with two ports, sothat the device is capable of sending and receiving data packets at eachport. Of course, devices of the network can also be multi-port bridgesor hubs, capable of routing a data packet over a specific port. For sucha router or switch, each port is also uniquely identified by its portidentifier or port number. Therefore, in a particularly preferredembodiment of the invention, the network descriptive informationaccumulated by a receiving device comprises a list of port identifiers,wherein each port identifier of the compiled list indicates the portfrom which a sending device broadcast the data packet received by thatreceiving device. In other words, for each port number of a receivingdevice, the receiving device lists the device identifier of the devicethat sent a message received at that port, as well as the port number ofthe port from which the sending device sent the message. This list ortable can be referred to as a ‘connectivity table’. A device that iscapable of accumulating and using such information is referred to as a‘learning bridge’.

A device of the network may possess only IP-router capability. In afurther preferred embodiment of the invention, therefore, the networkdescriptive information accumulated by a device comprises informationthat can be used to deduce the distances of other IP routers in relationto that device. For example, in order to collect network descriptiveinformation about other IP routers connected to a device, that devicecan broadcast a suitable message to a particular target device, andtrack the time it takes for the message to be returned from that targetdevice. The time taken for the message to pass from one IP router toanother on its way to the target device is also preferably tracked. Forexample, a device can issue a ‘traceroute’ message command, specifying aparticular device identifier as target. The message is forwarded by eachIP router until it reaches its target device. Each device along a pathenters its timestamp into the message body. When the target device isreached, it also enters its timestamp and returns the traceroute commandback to the originating device, which then extracts the timestampinformation. If the target device is not reached, a timeout occurs andthis information is also returned to the originator. The networkdescriptive information can then comprise an ‘elapsed time’ for each IProuter reached by the message. For example, if the traceroute command toa target device is returned to the originator after successful deliveryand after passing through two other intermediates device, the time takenfor the message to reach the target device will be longer than the timetaken for it to reach the intermediate devices. Equally, the time takenfor the message to reach the second intermediate device will be longerthan the time taken for it to reach the first intermediate devices. Fromthe network descriptive information collected by the originating device,it may therefore be concluded that the target device is further awayfrom the originator than the intermediate devices, and that the secondintermediate device is further away from the originator than the firstintermediate device. For example, measurements or calibrations in priorobservations may provide information about the time taken for a datapacket to be routed from one device to another along a wired connectionof an Ethernet network. The forwarding delay time of a data packet mighttypically comprise about 0.1 milliseconds, i.e. a packet might take 0.1milliseconds to pass from one device to the next. Using thisinformation, together with the compiled traceroute lists provided by thedevices of the network, the topology discovery unit can make reasonedestimates of the physical distances between devices in the network andcan use these to deduce the network topology.

A device of the network need not necessarily have routing capability.Instead, a device may simply be equipped with a single port forreceiving and sending messages or data packets. Such a device may stillbe identified by a unique address in that network, for example an IPaddress. A message returned by that device can include its IP address,thus identifying that device as having received and returned themessage. In a further preferred embodiment of the invention, therefore,the network descriptive information accumulated by a device comprises anelapsed time between an instant or timestamp at which a data packet wasbroadcast by a router (any bridge, switch or hub of the network) to atarget device and an instant at which the data packet—returned by theIP-addressable target device—was received by the originating device. Forexample, a router can issue a ping message command from one of itsports, and can then collect the returned message and extract anyIP-address and timestamp information from the returned message. In thisway, a switch or hub can easily accumulate or collect networkdescriptive information from the IP-addressable devices connected to oneof its ports. By analysing the network descriptive information collectedby the originating device, the distances of the IP-addressable devicesrelative to the originating device may be deduced in the networkdiscovery step.

The data packet to be sent by a sending device for the purpose ofcollecting network descriptive information is preferably assembledaccording to the capabilities of the receiving device(s). In aparticularly preferred embodiment of the invention, for devices withmessage routing capability, a data packet broadcast by a sending devicecomprises a port number of a port of that sending device from which thedata packet was broadcast and/or a device identifier of that sendingdevice.

In a network realised to communicate using a suitable local area networkprotocol such as Ethernet TCP/IP, it may be possible to exchangemessages between specific devices. Therefore, in a particularlypreferred embodiment of the invention, a data packet is received andconsumed by only one receiving device. Such a data packet can comprise aBridging Protocol Data Unit (BPDU) in a network based on the IEEE MACbridges standard (IEEE 802.1D) standard. A BPDU is sent from one routerto the next router, and contains—amongst others—the device identifier ofthe sending device as well as the port number of the sending device fromwhich the BPDU is sent. A BPDU message is sent from one device and‘consumed’ by the immediately neighbouring device, i.e. the deviceconnected to the port of the sending device from which the BPDU messagewas sent receives the message but does not forward it. Since a BPDUmessage contains the device ID of the sending device as well as the portidentifier identifying the port from which the message was sent, thereceiving device can easily compile a table with an entry for each ofits own port identifiers, whereby each entry is then augmented with thedevice ID and port identifier of its immediate neighbours. In anEthernet network, each device can have as many immediate neighbours asit has ports. For example, a router having two ports can have at mosttwo immediate neighbours. Therefore, the network descriptive informationcollected by a router in such a network preferably comprises aconnectivity table with the port number and device ID of the immediateneighbour on each port.

The network descriptive information collected by devices of thenetwork—whether bridges, IP-routers or IP-addressable devices—candirectly or indirectly deliver information about which devices are wiredtogether. Therefore, in a preferred embodiment of the invention, thestep of deducing the network topology comprises analysing the networkdescriptive information provided by the devices to identify neighbourdevices for each device of the network. For example, one or moresuitable algorithms can process the connectivity tables and/orforwarding tables and/or traceroute results and/or ping results etc. todeduce the network topology. Such algorithms may run on a processor of aprogrammable commissioning system. The choice of algorithm may depend onthe capabilities of the devices of the network and the quality of theaccumulated network descriptive information. Certain properties of thenetwork can assist in determining the topology. For example, the rootbridge can relatively easily be identified, since its connectivity tableor forwarding table will include all device identifiers of the devicesof the network. Similarly, multi-port bridges can also quickly beidentified, since these will generally have lists of device identifiersfor each of their ports. In contrast, a connectivity table or forwardingtable of a daisy chain terminating device will only have a list ofdevice identifiers for one of its ports. Once the network topology hasbeen discovered, this can be compared to the installation plan in orderto deduce which device identifier (and therefore which device) isassociated with a particular physical location descriptor.

To initiate the exchange of data packets with a view to collectingnetwork descriptive information, the commissioning system according tothe invention preferably comprises a device control interface forcontrolling the devices of the network to broadcast data packets. Thedevice control interface can be the same interface used to ultimatelycontrol the devices of the network according to a user's wishes. Thisdevice control interface can issue the appropriate number of commands ata suitable time, for example once the wiring has been complete, causingthe devices—according to their capability—to exchange data packets suchas BPDU messages, traceroute messages, etc. The device control interfacecan also control the devices to provide their accumulated or compilednetwork descriptive information (forwarding tables, connectivity tables,traceroute time results, ping time results, etc.) to the commissioningsystem.

Since the network may comprise devices with varying degrees ofcapability, for example the network may comprise some older devices aswell as more advanced devices, the device control interface ispreferably realised to control a device that comprises a router and/orto control a device that does not comprise a router. In this way,learning bridges can be controlled as well as more primitive devices,for example devices that are only IP-addressable but without anylearning capability.

Since there are differences in capabilities between routers, for exampleone type of router might be a learning bridge, able to compile aforwarding table, or even a more advanced connectivity table, whileanother type of router may only be able to forward messages, the devicecontrol interface of the commissioning system according to the inventionis realised to control a device comprising a bridge router and/or tocontrol a device comprising an internet protocol router.

The commissioning system, once it has collected all the networkdescriptive information, analysed this to discover the network topology,and compared the deduced network topology to the installation plan todetermine the physical location descriptor of each device identifier,preferably makes this known to a control system of the network, so thatspecific devices of the network can be controlled according to a user'swishes. Therefore, the commissioning system according to the inventionpreferably comprises a suitable interface for supplying a deviceidentifier and the physical location descriptor of the associated deviceto a control system. For example, the commissioning system can compile adatabase with a list of device identifiers, wherein each deviceidentifier is paired with a physical location descriptor. The list maybe organised in various ways, for example the physical locations of eachof the luminaires in one particular room may be grouped together in thelist (since it is usual to activate such a group of luminairescollectively) with their associated device identifiers. A lightingcontrol system, for example, can use the information provided toactivate or control the lights accordingly. Of course, a network mayalso comprise standalone bridges or routers that are not inside anydevice that is specifically controlled by the control system. Forexample, a lighting control system may only address devices that aredirectly related to the lighting, for example luminaires and switchesfor controlling the luminaires. Other routers in the network may becontrolled by other control systems, for example a heating controlsystem may be provided with a list of physical location descriptors anddevice identifiers of the thermostats of a building. An access controlsystem might be given a list of physical location descriptors and deviceidentifiers of transponders or fingerprint readers controlling the doorsof a building, etc.

Other objects and features of the present invention will become apparentfrom the following detailed descriptions considered in conjunction withthe accompanying drawings. It is to be understood, however, that thedrawings are designed solely for the purposes of illustration and not asa definition of the limits of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic representation of a floor plan of a building;

FIG. 2 is a schematic representation of a machine-readable installationplan;

FIG. 3 is a schematic representation of devices of a network beforenetwork discovery;

FIG. 4 is a block diagram of a bridge router;

FIG. 5 is a schematic representation of network descriptive informationaccumulated by devices of the network of FIG. 3;

FIG. 6 is a schematic representation the network of FIG. 3 after networkdiscovery;

FIG. 7 is a block diagram of a commissioning system according to anembodiment of the invention.

In the diagrams, like numbers refer to like objects throughout. Elementsof the diagrams are not necessarily drawn to scale.

DETAILED DESCRIPTION OF THE EMBODIMENTS

FIG. 1 shows a schematic representation of a floor plan 7 of a buildingwith rooms 70 arranged along a corridor 71. Each room 70 contains anumber of lights 80 and a light sensor 81, for example for sensing lightlevels with the room 70. Further lights are arranged in the corridor 71.The luminaires 80 and light sensors 81 are controllable by a lightingcontrol system for the building. To this end, each luminaire 80 andsensor 81 incorporates a router, which can be a simple two-port bridge10 or a multi-port bridge 11 or switch 11, as appropriate. For example,a luminaire 80 in a room 70 can incorporate a simple two-port bridge 10,while a luminaire in the corridor 71 can incorporate a switch 11 forpassing commands in more than two directions. Each bridge 10, 11 can berealised to control the power supply to its luminaire 80 or sensor 81,so that the luminaires 80 and sensors 81 of the building can beindividually and/or collectively controlled by the lighting controlsystem.

The bridges 10, 11 are wired together in an Ethernet network accordingto an installation plan 3, shown in FIG. 2. The installation plan 3indicates wired connections 32 to be made between certain pairs offittings, whereby a fitting can be luminaire or a sensor in thisexample. Fittings are indicated by appropriate symbols 30, 33, 34 suchas a luminaire symbol 30, 33 and a sensor symbol 34. Each wiredconnection is terminated at a port of a router, as indicated by the portsymbol 35. A root bridge can be indicated on the installation plan 3 byan appropriate symbol 36. Each fitting is identified by a physicallocation descriptor 31, which in this case comprises a code consistingof a number for each floor, room and fitting. For example, the luminairein the third room of the second floor, on the right and furthest awayfrom the door, can be indicated by a physical location descriptor 31comprising the ASCII character sequence “2.3.8”. Of course, this is onlya simple example, and for the sake of simplicity only a few suchphysical location descriptors are shown in the diagram. According to theplan 3, the bridges 10 of each room 70 are wired in a daisy-chainmanner, and one of the bridges 10 of each room is wired to a switch 11in the corridor 71. The switches 11 in the corridor 71 are also wired ina daisy-chain manner. In this way, all the devices that are to becontrolled can be wired together to give a network, whereby the rootbridge will be connected to the lighting control system. When wiring iscomplete, the network is powered up and enters the network topologydiscovery stage.

Initially, the commissioning system has no information about theindividual wired connections between the nodes or devices of thenetwork, as indicated in FIG. 3, which gives a schematic representationof some devices D1, . . . , D25 of a network N before network discoveryhas been performed.

FIG. 4 shows a simplified block diagram of a bridge router 10 with twoports 15. The bridge 10 is identified uniquely in that network by itsbridge identifier 14, which can be stored in a memory 101, for example amemory of a network interface card. Similarly, each port 15 of thebridge 10 is indentified by its own port identifier. A message can bereceived from or sent to a neighbouring device along a wired connection72. A processing unit 100 of the bridge 10 is realised to analyse areceived message and to assemble a message to be sent. The processingunit 100 can also control the fitting in which it is incorporatedaccording to the content of a received message, for example to connector disconnect the fitting from a power supply (not shown) by means of asuitable signal 102. The bridge 10 can collect network descriptiveinformation 40, 41, 42, 43 about its connectivity to other devices onthe basis of information extracted from received messages. The nature ofthe collected network descriptive information 40, 41, 42, 43 can dependon the realisation or capability of the bridge. For example, a learningbridge 10 can compile a connectivity table 40 and/or a forwarding table41. A learning bridge or an IP-router can assemble a traceroute list 42.The bridge 10 can also compile a ping table giving the round-trip timesfor ping messages sent from that device 10 to other devices in thenetwork. To determine how the devices are wired together, a devicecontrol interface issues appropriate commands that are propagatedthrough the system, beginning at the root bridge. Each bridge canreceive a message and can send a message. For example, in a preferredapproach, the device control interface can cause the devices to exchangeBPDU messages with destination address 01:80:C2:00:00:00, which is amulticast address for bridge management. This message is received by aneighbouring device, which records on which port the message arrived.The receiving device waits for a predetermined time and then issues aBPDU message from each of its ports. In time, each device of the networkwill have issued and received BPDU messages, and will have compileddevice identifier and port identifier information from each of itsneighbours. Of course, the other described techniques can also beapplied, in which the device control interface causes the devices tocompile forwarding tables, or to issue traceroute or ping messages.

FIG. 5 is a schematic representation of network descriptive information40, 41, 42, 43 accumulated by devices of the network of FIG. 3. Forexample, the device D2 has compiled a connectivity table 40. Each row ofthe connectivity table 40 has a field 401 for a port identifier of thedevice D2, a field 402 for the neighbouring device identifier 402, and afield 403 for the port identifier of the corresponding port of theneighbouring device. For the sake of simplicity, here and in thefollowing, the device identifier is indicated by the device referencenumber used in the diagram, whereas in reality a device identifier wouldcomprise an IP address or a MAC address. In this example, port #1 ofdevice D2 is wired to port #1 of device D1; port #2 of device D2 iswired to port #2 of device D9; and port #3 of device D2 is wired to port#2 of device D3. From this connectivity table 40, the network topologydiscovery unit can conclude that device D2 must be a multi-port bridgewith neighbouring devices D1, D9, D3.

Device D10 has compiled a forwarding table 41. Each row of theforwarding table 41 has an entry 411 for a port identifier of a port ofthe device D10, and an entry 412 for a list of device identifiers thathave sent messages received on that port. In this example, on its port#2, device D10 has received messages from devices D11, D12, D13. On itsport #1, device D10 has received messages from devices D9, D1-D3, D4-D9,D11-D25. From this connectivity table 40, the network topology discoveryunit can conclude that device D10 must be a two-port bridge, and thatonly three devices are located beyond the first port of the two-portbridge D10.

Device D1 has compiled a traceroute table 42. Each row of the traceroutetable 42 has an entry 421 for a device identifier, and an entry 422 forthe time accumulated by the message on its path via neighbouring devicesto a target device. In this example, device D1 has sent a traceroutemessage to device D7. Each intermediate device enters a timestamp intothe message. The completed message is returned to D1, which can thencompile its traceroute table 42. In this example, the traceroute messagetook 0.3 ms to reach device D4, 0.6 ms to reach device D5, 0.9 ms toreach device D6, and 1.2 ms to reach device D7 before being returned todevice D1. From this traceroute table 40, the network topology discoveryunit can conclude that device D4 is closest to device D1, device D5 isnext closest, etc.

Device D8 has compiled a ping table 43. Each row of the ping table 43has an entry 431 for a device identifier, and an entry 432 for the timetaken by the ping message to return to device D8. For the sake ofsimplicity, only two completed rows are shown. In this example, a pingmessage with device D5 as target took 0.9 ms to return from device D5. Aping message with device D1 as target took 1.2 ms to return from deviceD1. The ping table 43 therefore can give an indication of the relative‘distances’ between devices. Knowing that a forwarding delay comprisesabout 0.1 ms, the network topology discovery unit can deduce that, fromthe point of view of device D8, device D1 is further along a branch ofthe network than device D5. Of course, a ping table 43 delivers lessimmediately useful information than a connectively table 40 or aforwarding table 41, but can still be used to determine the position inthe network of a device that its only IP-addressable and which itselfcannot compile network descriptive information.

FIG. 6 shows the network of FIG. 3 after network discovery has beenperformed using the network descriptive information 40, 41, 42, 43collected by the devices D1-D25. Such a discovered topology can then beput to use by a commissioning system 5 according to the invention, asshown the block diagram of FIG. 7. The commissioning system 5 comprisesa memory 50 for storing a computer-readable installation plan 3, whichincludes physical location descriptors 31 of each wired device of thenetwork N. Of course, the installation plan can be provided over anysuitable source 50, for example it may be stored on a CD or DVD insertedinto a drive of a computer. A device control interface 55 is realised toassemble messages or frames to be sent via a root bridge of the networkN to other devices 10, 11, 12, 13 in the network, so that any message 2can be routed to a specific target device 10, 11, 12, 13 or broadcast toall devices 10, 11, 12, 13 of the network N. To initiate networkdiscovery, the device control interface 55 can cause the devices 10, 11,12, 13 of the network N to exchange messages 2, for example BPDUmessages 2, traceroute messages 2, ping messages 2 etc. Once thesemessages 2 have been exchanged by the devices 10, 11, 12, 13, the devicecontrol interface 55 can cause the devices 10, 11, 12, 13 to returntheir compiled network descriptive information 40, 41, 42, 43, which isextracted from the returned messages 2 by a data input unit 51. Atopology discovery unit 53 analyses the network descriptive information40, 41, 42, 43 to determine the network topology T. A commissioning unit54 compares the discovered network topology T to the installation plan 3and determines which physical location descriptor 31 is associated witha particular device identifier 14. For example, using FIG. 1, FIG. 2 andFIG. 6, the commissioning unit 54 can deduce that the devices D19-D24are the six lights of the larger room of FIG. 1, and that device D24 isthe terminating device of the daisy chain, with physical locationdescriptor “2.6.5”. Similarly, it can easily be deduced that device D1is directly connected to the root bridge D25. Physical locationdescriptor/device identifier pairs can then be output over a suitablecontrol system interface 56 to a control system 8, for example alighting control system 8, which can use the information to controldevices of the network individually, in groups, or collectively,according to a user's requirements.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, such illustration and descriptionare to be considered illustrative or exemplary and not restrictive; theinvention is not limited to the disclosed embodiments. Other variationsto the disclosed embodiments can be understood and effected by thoseskilled in the art from a study of the drawings, the disclosure, and theappended claims. For example, although the method according to theinvention is ideally suited to performing commissioning for a wirednetwork, some wireless devices could also be considered, for example ashort-range wireless device whose position in the network can be deducedfrom messages exchanged between it and another wired device.

For the sake of clarity, it is to be understood that the use of ‘a’ or‘an’ throughout this application does not exclude a plurality, and‘comprising’ does not exclude other steps or elements. The mere factthat certain measures are recited in mutually different dependent claimsdoes not indicate that a combination of these measures cannot be used toadvantage. Any reference signs in the claims should not be construed aslimiting the scope.

1. A method of performing automatic commissioning of a networkcomprising a plurality of network devices for lighting a building,wherein the devices are realised to exchange data packets, which methodcomprises the steps of: receiving an installation plan for the network,which installation plan comprises a physical location descriptor fordevices of the network, wherein each device is characterised by a deviceidentifier; issuing broadcast commends for a predetermine time to eachdevice to broadcast data packets to other devices; accumulating, duringthe predetermine time by each device, network descriptive informationbased on communication information related to data packets exchangedbetween the devices, wherein the network descriptive informationidentifies neighboring devices for each device of the network andincludes one or more of a list of sending/receiving device portidentifiers, forwarding tables, connectivity tables, traceroute timeresults, and ping time results; analysing the accumulated networkdescriptive information from each device to deduce a network topology ofthe entire network by estimating distances between each device using thenetwork descriptive information; allocating a physical locationdescriptor to each device identifier in the network topology bycomparing the network topology to the installation plan, by pairing adevice identifier with a physical location descriptor by deduction;grouping devices based on their physical locations or function,commissioning the network by providing the device identifiers, physicallocation descriptors and groups to a control system to control a device.2. The method according to claim 1, wherein the network descriptiveinformation accumulated by a device comprises an elapsed time between aninstant at which a data packet was sent from a sending device and aninstant at which the data packet was received by that device.
 3. Themethod according to claim 1, wherein a data packet is received andconsumed by only one receiving device.
 4. The method according to claim3, wherein the receiving device is an immediate neighbour of the sendingdevice.
 5. A commissioning system for automatically commissioning anetwork comprising a plurality of wired network devices for lighting andclimate control of a building, wherein the devices are realised toexchange data packets, which commissioning system comprises: a memory toreceive a computer-readable installation plan for the network, whichinstallation plan comprises a physical location descriptor for eachdevice of the network, wherein each device is characterised by a deviceidentifier and wherein the plurality of network devices includes atleast two or more of a light or luminaire, light switch, light sensorand thermostat; a device control interface to issue broadcast commendsfor a predetermine time to each device to broadcast data packets toother devices, accumulate network descriptive information provided byeach of the devices, wherein the network descriptive information isbased on communication information related to data packets exchangedbetween the devices, and wherein the network descriptive informationidentifies neighboring devices for each device of the network andincludes one or more of a list of sending/receiving device portidentifiers, forwarding tables, connectivity tables, traceroute timeresults, and ping time results; a topology discovery unit to derive thenetwork topology of the entire network from the provided networkdescriptive information-by estimating distances between each deviceusing the network descriptive information; and a commissioning unit toallocate a physical location descriptor to each device identifier in thenetwork topology, wherein the commissioning unit compares the derivednetwork topology to the installation plan by pairing a device identifierwith a physical location descriptor by deduction and groups devicesbased on their physical locations or function.
 6. The commissioningsystem according to claim 5, wherein the device control interface isrealised to control the devices of the network to exchange data packets.7. The commissioning system according to claim 6, wherein the devicecontrol interface is realised to control devices of a wired network. 8.The commissioning system according to claim 5, wherein the devicecontrol interface is realised to control a device comprising a bridgerouter and/or to control a device comprising an Internet Protocolrouter.
 9. The commissioning system according to claim 5, comprising acontrol system interface for supplying a device identifier and thephysical location descriptor of the device associated with that deviceidentifier to a control system.
 10. A computer program product, fixed ina tangible medium, when run on a processor of a programmablecommissioning system for a method of performing automatic commissioningof a network comprising a plurality of network devices for lighting abuilding, wherein the devices are realised to exchange data packets, thecomputer program product comprises code for: receiving an installationplan for the network, which installation plan comprises a physicallocation descriptor for devices of the network, wherein each device ischaracterised by a device identifier; issuing broadcast commends for apredetermine time to each device to broadcast data packets to otherdevices; accumulating, during the predetermine time by each device,network descriptive information based on communication informationrelated to data packets exchanged between the devices, wherein thenetwork descriptive information identifies neighboring devices for eachdevice of the network and includes one or more of a list ofsending/receiving device port identifiers, forwarding tables,connectivity tables, traceroute time results, and ping time results;analysing the accumulated network descriptive information from eachdevice to deduce a network topology of the entire network by estimatingdistances between each device using the network descriptive information;allocating a physical location descriptor to each device identifier inthe network topology by comparing the network topology to theinstallation plan, by pairing a device identifier with a physicallocation descriptor by deduction; grouping devices based on theirphysical locations or function, and commissioning the network byproviding the device identifiers, physical location descriptors andgroups to a control system to control a device.
 11. The method accordingto claim 1, wherein the one or more communication information tables foreach device includes one or more of: a connectivity table, a forwardingtable, a traceroute table, and a ping table.
 12. The method according toclaim 1, wherein the network descriptive information is accumulated bythe devices of the network based on data packets exchanged by thedevices.
 13. The method according to claim 12, wherein the networkdescriptive information accumulated by a receiving device comprises alist of device identifiers, wherein each device identifier of the listindicates the device that sent a data packet received by that receivingdevice.
 14. The method according to claim 13, wherein the networkdescriptive information accumulated by a receiving device comprises alist of port identifiers, wherein each port identifier of the listindicates the port from which a device sent a data packet received bythat receiving device.
 15. The method according to claim 1, wherein thecontrol system is a digital addressable lighting interface (DALI)system.
 16. The method according to claim 1, wherein the commissioningstep includes, grouping the devices in a portion of the buildingaccording to their physical locations, and controlling the devices usingthe device identifiers based on the group.
 17. The method according toclaim 1, wherein the issuing broadcast commends includes issuing aBridging Protocol Data Unit (BPDU) packet based on IEEE MAC bridgesstandard (IEEE 802.1D) standard.
 18. The method according to claim 1,wherein network descriptive information identifies neighbouring devicesfor each device of the network by tracking a time a broadcast messagetakes be returned to an originating device from a target device, whereinthe time taken for the broadcast message to pass from one IP router toanother on its way to the target device is tracked, wherein thebroadcast message is forwarded by each IP router until it reaches thetarget device, wherein each device along a path enters a timestamp intothe broadcast message body, wherein when the target device is reached,the target device enters a timestamp and returns a traceroute commandback to the originating device, originating device extracts thetimestamp information, and wherein if the target device is not reached,a timeout occurs and returned to the originating device, and wherein thenetwork descriptive information includes an elapsed time for each IProuter reached by the broadcast message.
 19. The method according toclaim 1, wherein network descriptive information identifies neighbouringdevices for each device of the network by having device comprise a listof port identifiers, wherein each port identifier of the compiled listindicates a port from which a sending device sent a broadcast messagereceived by a receiving device, wherein, for each port number of areceiving device, the receiving device lists a device identifier of anoriginating device that sent a message received at that port, as well asa port number of a port from which the sending device sent the message.